An ECE mechanism in which chemical reaction is permanently in equilibrium is investigated theoretically. The calculations were performed by the method of numerical integration for fast and reversible electrode reactions as well as for the reactions that are controlled by the electron transfer kinetics. In square–wave voltammetry the response depends on the difference in standard potentials of individual electron transfers and on the dimensionless equilibrium constant of the chemical reaction. Depending on the concentration of compound X–, which is one of reactants in chemical reaction, either a single peak or the split response may appear. In the first case the peak potential depends linearly on the logarithm of X– concentration, with the slope –2.3RT\2F. The potential of the first peak of the split response is also linear function of, but the slope is –2.3RT\F. The relationship is determined between standard potentials and the critical value of the equilibrium constant above which the response splits in two peaks. Under the influence of electrode kinetics, the responses change with square–wave frequency. The first electron transfer is slow and the second one is fast if two peaks appear at the lowest frequency and merge into a single peak at the highest frequency. If the second charge transfer is slower that the first one, the difference in peak potentials increases with the increasing frequency.

A cunent–mode square–root domain filter based on a new geometric–mean circuit is presented– The circuit is a tunable first–orfur low pass filter, working in lotv voltage, and feattting low nonlinearity. It employs MOSFETs that operate in both strong...

Modernism, as one of the main achievements of man, has been the source of various changes in the spatial structure and function of cities. Among the changes, city square –asa space supplying part of social life covers a wide range of urban functions...

Lichen species (Hypogymnia physodes and Evernia prunastri) were used for biomonitoring the possible air pollution with heavy metals in the vicinity of copper mine in the eastern part of the Republic of Macedonia. The contents of 18 elements were analysed by ICP–AES and ETAAS techniques. For data processing basic statistical methods and multivariate exploratory (factor and cluster analysis) techniques were applied. Three geogenic and one anthropogenic group of elements were singled out from factor analysis. Maps of spatial distribution of elements from the anthropogenic group showed an increased content of the anthropogenic elements only in close vicinity to the mine. A maximum value obtained for Cu content was 130 mg\kg and for Pb content was 120 mg\kg. Lichen talus of the collected species showed high retention power for accumulation of the anthropogenic group of elements compared to moss species sampled from the same study area (r=0.86 and r=0.68). Here we show that lichens can be use as biomonitors for atmospheric distribution of anthropogenicintroduced elements.

Heavy metal contamination afects large areas of Iran and worldwide. Hot spots of pollution are located close to industrial sites, around large cities and in the vicinity of mining and smelting plants. Agriculture in these areas faces major problems...

Chenopod shrubs accumulate Na, K and Cl. There is little information available on the factors affecting the accumulation of these and other minerals in these plants. A field experiment was conducted out to study the accumulation of Na, Cl, K, N, Ca,...

The aim of the study is to determine the major source and extent of metal pollution in the vicinity of Dashkasan gold mine. Dashkasan mine has resulted in extensive contamination of soils by Arsenic (As) and potentially toxic ore–related elements...

Concentrations of Zn, Cu, Cr, Cd, Pb and Fe in surface marine sediments of the southern coast of Sfax were studied in order to understand current metal contamination at the outlet of a mixed industrial and domestic wastewater effluent discharged into...

A study of the atmospheric particulate size distribution of total suspended particulate matter (TSPM) and associated heavy metals concentrations has been carried out for the urban part of Sarajevo city, Bosnia and Herzegovina. Urban particles (n=150) were collected using a high volume air sampler equipped with a 6–stage impactor. Apart from Fe which has been determined by flame atomic absorption spectrometry (FAAS), all measurements (Co, Cu, Mn) have been carried out by graphite furnace atomic absorption spectrometry (GFAAS). The average concentrations of particulate matter are 37%, 18%, 15%, 8%, 15% and 6% (averaged over all the observations) of total suspended particulate for PM 0.49, PM0.95 – 0.49, PM1.5 –0.95, PM3.0 – 1.5, PM7.2 – 3.0 and PM> 7.2, respectively. Metal concentrations in size–fractionated urban particles ranged from 0.01–3.83 ng\m3 for Co, 6.30–179.20 ng\m3 for Cu, 5.00–208.70 ng\m3 for Mn and 0.35–6.82 g\m3 for Fe. Major concentrations of investigated metals are associated with the PM 7.2–3.0 μm. Overall, the decreasing trend of average trace element concentrations (24–h) in the particulates revealed the following order: Fe>Mn>Cu>Co.

Employing a recently introduced framework within which a large number of classical aud modern adaptive filter algorithms can be viewed as pecial cases, we have developed a generic variable step–size adaptive filter. Variable Step–Size normalized...

Size and shape of fruit are the most important quality parameters for evaluation by consumer performance. Also misshapen fruits are usually rejected according to grading standards of fruit.This research was conducted to determine quantitative...

One of the most notable challenges in oil engineering is the produced water from oil reservoirs. The process of eliminating this water, besides increasing costs and decreasing efficiency of oil production, causing a decline of utilization capacity...

In the recent years, the synthesis of metal nanoparticles has received much attention due to its wide range ofapplications in various fields. Among metallic nanoparticles, copper and copper oxide nanoparticles have attractedmuch attention of...

Stagnation flow of an electrically conducting incompressible viscous fluid towards a moving vertical plate in the presence of a constant magnetic field is investigated. By using the appropriate transformations for the velocity components and temperature, the partial differential equations governing flow and heat transfer are reduced to a set of nonlinear ordinary differential equations. These equations are solved approximately using a numerical technique for the following two problems: (i) two–dimensional stagnation–point flow on a moving vertical plate, (ii) axisymmetric stagnation–point flow on a moving vertical plate. The effects of nondimensional parameters on the velocity components, wall shear stresses, temperature and heat transfer are examined carefully.

In the present paper, the effect of effective thermal conductivity on natural convection heat transfer in threelayer porous cavity are analyzed using a collocated control volume formulation and a SIMPLT algorithm for pressure–velocity coupling....

The Stirling engine is an external combustion engine that works with any heat source. Surrounded by heating with gas pressure to the piston displacement and cooling gas, the piston reaches the initial point. This paper explores the Laminar flow...

The steady, incompressible micropolar fluid flow over a stretchable disk has been investigated. The governing partial differential equations have been transformed in to ordinary differential form by using similarity transformations. The resulting...

The boundary layer flow of a third grade fluid and mass transfer near a stagnation–point with diffusion of chemically reacting species on a porous plate is investigated. Due to a porous plate the suction is taken into an account. Using suitable...

The freezing–thawing effect on the meat quality of whole, gutted and fillets of sea bass (Dicentrarchus labrax) were investigated. It was aimed to investigate the changes in the meat quality of whole, gutted and fillets of sea bass in multiple frozen (–18±2ºC) and thawed cycles in refrigerated conditions (4±2°C). The meat quality assessment of the sea bass groups (whole, gutted and fillets) subjected to multiple freeze and thaw cycles was performed by monitoring sensory quality, chemical analysis such as pH, total volatile basic nitrogen (TVB–N), trimethylamine nitrogen (TMA–N), thiobarbituric acid (TBA), crude protein and lipid content. The length of the thawing process caused quality changes such as dryness of the skin and undesirable odor formation. Thus the sea bass groups reached unacceptable levels after the 5th freeze\thaw process. According to the sensorial evaluation, no significant differences (P>0.05) were found in general acceptability values among the sea bass groups thawed under refrigerator conditions, but there was a significant difference in pH, TVB–N, TBA and crude protein (P0.05) results. Significant differences (P0.05) in TMA–N concentrations and crude fat were observed between the whole and gutted samples and also between the whole and fillet samples.

The objective of this study is to produce maximum hydrogen from advanced alkaline electrolyzer. The input electricity of electrolyzer is generated with wind turbine. The wind turbine is utilized with a self–exited induction generator. The effect of...

A field study was undertaken to investigate the effects of two stocking systems on the concentration of water–soluble carbohydrates (WSC) reserves of Bromus tomentellus, Cephalaria kotschyi and Ferula haussknechtii through two growth cycles in Saral...

This study describes the effects of different stocking densities on texture\colour characteristics, protein content \amino acid and lipid content\fatty acid composition of rainbow trout ﬁllet. Stocking density was selected 5 (Group A), 15 (Group B), 25 (Group C) kg fish m−3. Tukey’s Multiple Comparison Test showed insigniﬁcant differences between measured size\weight measurement and condition factors. No significant differences were found between A and C groups for colour analysis (L* and a* value) and texture profile analysis (hardness, adhesiveness, cohesiveness and gumminess values) of rainbow trout fillets. The proximate composition analysis showed rainbow trout ﬁllets from the A and C groups to exhibit higher values of moisture than the B group. Fish from the A and B groups had a lower of ash and protein in comparison to C group samples. The highest fat values of rainbow trout were measured in B group samples. The content essential amino acid and non–essential amino acid was lower in A and B groups than in C groups. Fish from the C group had higher content of polyunsaturated fatty acids, especially n–3, docosahexanoic acid (DHA) and eicosapentaenoic acid (EPA) in comparison to A and C group. As a result, 25 kg fish m−3 is recommended stock density in terms of product texture\color and composition quality.

White cheese is one of the most important dairy products manufactured, marketed and consumed in Egypt. To study differences in the composition and sensory properties of local white cheese, forty two cheese samples were collected from different...

This study was conducted to evaluate the effects of dietary levels of vitamins E (25, 30 and 35 mg kg–1), Folic Acid (1.5, 2 and 2.5 mg kg–1) and their combination on the growth performance, hematological and immunological parameters of rainbow...

This study evaluated the suitability of canola oil as a source of supplemental dietary lipid for rainbow trout. Triplicate groups of the 30 fingerlings held under identical culture conditions were fed twice daily by iso–nitrogenous, iso–calorific and...

Apricot (Prunus armeniaca L.) is a species particularly prone to erratic fruit set, and its flower bud drop has been repeatedly reported in different cultivars and growing conditions. A number of potential causes have been explored, but a clear main cause remains elusive. In this study, fruit set was determined for 11 apricot cultivars (‘Precoce de Tyrinthe’, ‘Feriana’, ‘Beliana’, ‘Priana’, ‘Bebeco’, ‘Early Kishinewski’, ‘Precoce de Colomer’, ‘Canino’, ‘Silistre Rona’, ‘Rouge de Sernhac’ and ‘Tokaloglu’) grown on the coast of the Mediterranean region of Turkey from 2006 to 2008. Trees budded on apricot seedlings and planted 6×6 m in 1997. On four branches of each tree randomly selected from all four directions, blossom number, percentage of initial and final fruit set, and yield per tree were determined during the experimental period. Fruit set differed significantly depending on year and cultivar. Based on three–year averages, percentage of fruit set was highest on ‘Tokaloglu’ (14%), followed by ‘Beliana’ (8.8%) and ‘Precoce de Tyrinthe’ (8.2%). The lowest fruit set (2.3%) was in ‘Early Kishinewski’ and ‘Canino’. High yields per tree were found in Tokaloglu’ (29.1 kg), ‘Precoce de Tyrinthe’ (29.0 kg), ‘Rouge de Sernhac’ (27.9 kg), and ‘Beliana’ (23.0 kg). ‘Tokaloglu’, ‘Beliana’, ‘Precoce de Tyrinthe’, and ‘Rouge de Sernhac’ cultivars showed good performance for both fruit set and yield per tree under subtropical climate conditions. However, findings of this study also suggested that fruit set and fruit drops in apricots should be assessed together with total yield amounts by years. The influence of the cultivar on fruit yield was more determinant than the seasonal effect.

Conventional overbalanced drilling (OBD) mostly results in several problems in Naturally Fractured Reservoirs (NFR). Formation damage and lost circulation are two main problems associated with OBD in NFR which consequently result to decrease the...

Taking into account that in many construction projects in Iran operatives are paid based on hours of presence on sites, any wasted time equals loss of revenue for the contractors by adversely affecting the productivity on sites. On the other hand,...

The goal of this study is to investigate the factors creating work motive inorganizations. The hypothesis of the study is that there is a direct andsignficant relation between increased motive and higher productivity. Themethod to implement the study...